Exploring Mechanisms and Morphology of QT Interval Prolongation

Not Applicable

Completed

• Conditions: Sudden Cardiac Death; Long Qt Syndrome 1-2
• Interventions: Drug: Beta Blockers; Drug: Spironolactone

• Registration Number: NCT03291145
• Lead Sponsor: Herlev and Gentofte Hospital

Brief Summary

The projects will try and optimise the risk stratification for patients with Long QT syndrome by investigating how the exposure of physical and acoustic stress will affect the QT-dynamics and if beta blockers protect against arrhythmias by suppressing this dynamic QT-prolongation. Furthermore, the project will investigate the effects of Spironolactone on the QT-dynamics tested by "Brisk Standing".

First, patients are tested with known arrhythmic triggers and they are then administered thier normal dose of beta blockers. Hereafter, "Brisk Standing" test is performed and the patients are on Spironolactone for seven days. After seven days treatment the "Brisk Standing" is repeated.

Detailed Description

The aim of the projects is to try and optimise the risk stratification for patients with Long QT syndrome by investigating how the exposure of physical and acoustic stress will affect the QT-dynamics and if beta blockers protect against arrhythmias by suppressing this dynamic QT-prolongation. Furthermore, the project will investigate the effects of Spironolactone on the QT-dynamics tested by "Brisk Standing".

First, patients are tested with known arrhythmic triggers and they are then administered thier normal dose of beta blockers. Hereafter, "Brisk Standing" test is performed and the patients are on Spironolactone for seven days. After seven days treatment the "Brisk Standing" is repeated.

Study Timeline

• Study Start: 2017-06-27
• Study First Submitted: 2017-08-14
• Study First Submitted QC: 2017-09-21
• Study First Posted: 2017-09-25
• Primary Completion: 2018-06-27
• Study Completion: 2019-01-01
• Status Verified: 2019-02
• Last Update Submitted: 2019-02-20
• Last Update Posted: 2019-02-21

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 28

Inclusion Criteria

• Verified Long QT syndrome mutation, subtype 1 or 2.
• over 18 years of age

Exclusion Criteria

• Atrioventricular block,
• Left bundle branch block,
• Left ventricular hypertrophy,
• Pace rhythm,
• ST-deviations >1 mm),
• Left ventricular ejection fraction <50 % and significant valvulopathy,
• Unstable psychiatric disease
• Unstable cardiovascular disease.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Beta Blockers	Beta Blockers	With and without Beta Blockers
Spironolactone	Spironolactone	With and without Spironolactone

Primary Outcome Measures

Name	Time	Method
QTc	7 days	Corrected QT

Trial Locations

Locations (1)

Herlev-Gentofte Hospital; 🇩🇰 Herlev, Copenhagen, Denmark